Accel bought into Mark Zuckerberg's global empire when it was just a humble Ivy League redoubt. That $12.7 million investment has paid off nicely, at least according to Goldman Sachs' most recent share purchase that values the company at $50 billion.

Accel was in on a $5.5 million Series A fundraising round for the online video behemoth. In 2007, the company would raise another $59.5 million in a Series C capital raise. The company has said it expects to go public as soon as 2011, which is this year!

In 2009, Accel bought a stake in the highly successful group discount site during a $30 million investment round. Late last year, Groupon and its talking-cat mascot reportedly turned down a $6 billion takeover bid from Google.